def test_triangle_and_segment_are_parallel(self):
A = Point3D(0, 0, 0)
B = Point3D(1, 0, 0)
C = Point3D(0, 1, 0)
triangle = Triangle3D(A, B, C)
S = Point3D(0., 0.5, 1)
T = Point3D(0.5, 0., 1)
segment = Segment3D(S, T)
with self.assertRaisesRegex(ValueError, 'There is no intersection'):
intersec3d_triangle_segment(triangle, segment)
def test_no_intersection(self):
A = Point3D(0, 0, 0)
B = Point3D(1, 0, 0)
C = Point3D(0, 1, 0)
triangle = Triangle3D(A, B, C)
S = Point3D(0.25, 0.25, -1)
T = Point3D(0.25, 0.25, -0.5)
segment = Segment3D(S, T)
with self.assertRaisesRegex(ValueError, 'There is no intersection'):
intersec3d_triangle_segment(triangle, segment)
def test_triangle_and_segment_are_in_same_plane(self):
A = Point3D(0, 0, 0)
B = Point3D(1, 0, 0)
C = Point3D(0, 1, 0)
triangle = Triangle3D(A, B, C)
S = Point3D(0., 0.5, 0)
T = Point3D(0.5, 0., 0)
segment = Segment3D(S, T)
msg = 'Triangle and segment are in the same plane'
with self.assertRaisesRegex(ValueError, msg):
intersec3d_triangle_segment(triangle, segment)
def test_triangle_is_a_point(self):
A = Point3D(0, 0, 0)
B = Point3D(0, 0, 0)
C = Point3D(0, 0, 0)
triangle = Triangle3D(A, B, C)
S = Point3D(0.25, 0.25, -1)
T = Point3D(0.25, 0.25, 1)
segment = Segment3D(S, T)
msg = 'Triangle is degenerated \(a segment or point\)'
with self.assertRaisesRegex(ValueError, msg):
intersec3d_triangle_segment(triangle, segment)
def test_intersection_in_triangle(self):
"""
C T y ^
| - / | z
| I - |/
A--/--------B +-----> x
S
"""
A = Point3D(0, 0, 0)
B = Point3D(1, 0, 0)
C = Point3D(0, 1, 0)
triangle = Triangle3D(A, B, C)
S = Point3D(0.25, 0.25, -1)
T = Point3D(0.25, 0.25, 1)
segment = Segment3D(S, T)
I = intersec3d_triangle_segment(triangle, segment)
self.assertEqual(I.x, 0.25)
self.assertEqual(I.y, 0.25)
self.assertEqual(I.z, 0.)